They crafted the VoiceXML standards that were broadly adopted by industry, and these standards are still the technology recommended today. A role of primary importance was played by the W3C Voice Browser Working Group (VBWG). In the 1990s, the landscape of speech and DTMF applications changed from being based on proprietary languages to being completely based on speech standards. When the Internet came along, the adoption of HTML and public standards demonstrated that using a similar model could lead to voice applications that were more open and flexible. Back in the day, IVR technology was proprietary, limiting its usefulness, and developing IVR applications was cumbersome. What drove the need for VoiceXML? Several things. As an XML-based language that describes the voice interface and allows for audio input and output, VoiceXML makes it easy for developers to create voice-enabled applications. With VoiceXML, application developers create audio dialogs that feature synthesized speech, digitized audio, recognition of spoken and DTMF key input, recording of spoken input, telephony, and mixed initiative conversations. VoiceXML is a standardized scripting language used for creating voice services such as interactive voice response (IVR) applications.

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